body {
    width: 100%;
    max-width: 640px;
    min-width: 320px;
    margin: 0 auto;
    background-color: #fff;
    font-size: 14px;
    font-family: -apple-system, Helvetica, sans-serif;
    line-height: 1.5;
    color: #666;
}
ul {
    margin: 0;padding: 0;
    list-style: none;
}
img {
    vertical-align: middle;
}
/* CSS3盒子模型 */
div {
    box-sizing: border-box;
}
a {
    color: #666;
    text-decoration: none;
}
*{
    -webkit-appearance-color: none;
}
input {
    -webkit-appearance: none;
}
img,
a {
    -webkit-touch-callout: none;
}

    /* 顶部start */
.JDApp {
    height: 45px;
}

.JDApp ul li {    
    float: left;
    text-align: center;
    line-height: 45px;
    height: 45px;
    background-color: #333;
    color: #fff;
}

.JDApp ul li:nth-child(1){
    width: 8%;
}
.JDApp ul li:nth-child(1) img{
    width: 10px;
}
.JDApp ul li:nth-child(2){
    width:10%;
}
.JDApp ul li:nth-child(2) img{
    width: 30px;
    /* 图片和文字默认是基线对齐 */
    vertical-align: middle;
}
.JDApp ul li:nth-child(3){
    width: 57%;
}
.JDApp ul li:nth-child(4){
    width: 25%;
    background-color: #F63515;
}
/* 顶部End */

/* 搜素Start */
.search-wrap {
    overflow: hidden;
    /* 固定定位 */
    position: fixed;
    width: 100%; 
    height: 44px;
    text-align: center;
    line-height: 44px;
    max-width: 640px;
    min-width: 320px;
}
.search-bth {
    position: absolute;
    top: 0;
    left: 0;
    width: 40px;
    height: 44px;
}

/* .search-bth img{
    width: 30px;
    vertical-align: middle;
} */

.search-bth::before {
    content: "";
    display: block;
    width: 20px;
    height: 18px;
    background: url(../images/s-btn.png) no-repeat;
    background-size: 20px 18px;
    margin: 14px 0 0 15px;
}
.search-login {
    position: absolute;
    top: 0;
    right: 0;
    width: 40px;
    height: 44px;
    color: #fff;
}
.search {
    position: relative;
    height: 34px;
    background-color: #fff;
    margin: 0 50px;
    border-radius: 15px;
    margin-top: 7px;
}

.JD-icon {
    position: absolute;
    width: 20px;
    height: 15px;
    top: 8px;
    left: 13px;
    background: url(../images/jd.png) no-repeat;
    background-size: 20px 15px;
}
.JD-icon::after {
    content: '';
    position: absolute;
    right: -10px;
    display: block;
    width: 1px;
    height: 15px;
    background-color: #CCC;
}
.search-icon {
    position: absolute;
    top: 8px;
    left: 50px;
    width: 18px;
    height: 15px;
    /* 此处注意精灵图在缩放页面如何获取 称为二倍精灵图做法 */
    /* 先将精灵图等比例缩放成一半大小 
    再去测量要的icon坐标
    代码里,background-size也要写原来宽度的一半*/
    background: url(../images/jd-sprites.png) no-repeat -81px 0;
    background-size: 200px auto;
}
/* 搜素End */

/* 轮播图部分Start */
.slider img {
    width: 100%;
}
/* 轮播图部分End */

/* 品牌日Start */
.brand {
    overflow: hidden;
    border-radius: 10px 10px 0 0 ;
}
.brand div {
    float: left;
    width: 33.33%;
}

.brand div img {
    width: 100%;
}

/* 品牌日End */

/* nav部分Start */
nav {
    padding: 5px;
}
nav a {
    float: left;
    width: 20%;
    text-align: center;
}

nav a img {
    width: 40px;
    margin: 10px auto;
}

nav a span {
    display: block;
}
/* nav部分End */

/* news模块Start */
.news {
    margin-top: 20px;
}
.news a {
    float: left;
}
.news img {
    width: 100%;
}
.news a:nth-child(1) {
    width: 50%;
}
/* .news a:nth-child(2),
.news a:nth-child(3) {
    width: 25%;
} */
 /* n+2 就是从0+2个往后选 */
 .news a:nth-child(n+2) {
    width: 25%;
    border-left: 1px solid #CCC;    
    box-sizing: border-box;
 }
/* news模块End */